I've inherited a server and had some issues upgradeing via Yum. Issue with multilib versions on libmxl2. for some reason previous admin has installed a later version of libxml2 than available from teh repo's.

Can anyone advise a safe way to downgrade to correct centos 6.10 version?

tried yum distro-sync but this didn;t work. looks as though previous admin was using city-fan repo.. which is not recommended.. It's not listed in repolist
but still this package remains after disto-sync.. any tips?

The city-fan repo is a disaster of monumental proportions and should be avoided.

You'll need to disable and remove the city-fan repo before you start then try using yum downgrade libxml2 though we do not supply a python*-libxml2 package and you may need to remove that before you try.